In a manufacturing process of a semiconductor device, various kinds of film forming processes of forming, e.g., insulating films, an etching process of etching, e.g., these insulating films, and so forth are performed in a depressurized processing vessel provided in a substrate processing apparatus such as a plasma processing apparatus. In this depressurized processing vessel, fine particles caused by, for example, sputtering of plasma generated in the processing vessel or resulted from reaction products generated by a reactant gas may adhere to the inside of the depressurized processing vessel. If these particles adhere to a substrate, a production yield may be deteriorated. In order to solve this problem, the substrate processing apparatus is required to have high degree of cleanliness.
As a way to clean the inside of the processing vessel, Patent Document 1, for example, describes a method of dispersing particles within the processing vessel by using a shock wave of a gas generated when the gas is introduced into the processing vessel, an electromagnetic stress generated when a high voltage is applied, or the like.
Further, as a way to evaluate the cleanliness within the processing vessel, there is proposed, for example, a method of supplying a purge gas into the processing vessel and counting particles separated from the processing vessel due to the supply of the purge gas by using a particle monitor (Patent Document 2).
Just by counting the particles, however, it is difficult to identify a particle source from which the particles are generated. Thus, a generation amount of the particles cannot be reduced. For this reason, typically, in the aforementioned substrate processing apparatus, analysis of components of the particles adhering to the substrate or analysis of distribution of each component on the substrate has been conducted in order to identify the particle source (Patent Document 3).
Patent Document 1: Japanese Patent Laid-open Publication No. 2005-101539
Patent Document 2: Japanese Patent Laid-open Publication No. 2005-317900
Patent Document 3: Japanese Patent Laid-open Publication No. H10-326812